Home Open Account Help 244 users online

Steam & Excursion > C&O H-8 question


Date: 01/21/23 11:06
C&O H-8 question
Author: train1275

Reading up  a little on the C&O''s 2-6-6-6 Class H-8 locomotives built by Lima, and the T-1 Class 2-10-4 engines, and got to wondering if C&O would have been as well off getting more T-1's instead of going with the H-8's ?  Anyone have thoughts on that ?  What big locomotives, 778,000 lbs and massive tractive effort in the 110,000 - 119,000 lbs. range, but from stats I am reading not really utlilized much more than a T-1. 

 



Date: 01/21/23 12:16
Re: C&O H-8 question
Author: wcamp1472

In my opinion, the 2-10-4s designs were out-dated, poorly suited to the changing
traffic scene and had too much power applied to thier main rods. ..all that piston
thrust applied through the center 2 dtiving axles and crankpins ...
.Also, the whirling counterweights for so massive a machine were brutal on
pounding the track structure, when at any decent track speed.  
The ATSF 2-10-4s with thie bigger drivers were a better design of the
2-10-4 arrangement.

The 2-6-6-6, by dividing the piston thrusts into 4 medium sized pistons
and smaller counterweights for 3 coupled axles are much lighter,
and they're power thrusts are non-synchronized, which is easier on the 
rail infrastructure.

Their utilization on heavy, slow drag-freights was unfortunate train assignments 
by C&O.  But, MOST of their business was from coal and coal empties.
The 2-6-6-6s were like race horses, harnessed to bulky oversized wagons.

The UP/ALCO designed 4-6-6-4 was a better all-around design for true 
'general purpose' applications; also, exemplified by the N&W 'A' class, 2-6-6-4.

Either one could have been substituted for the 2-6-6-6. 
However, I'd LOVE to see an H-8 restored. and on the road, earning its keep.

That  big grate area means plenty of steam, for speeds in the 70s, with
heavy trains.  Chessie's whole approach to railroading would have had
to be re-built from the bottom up ( emulating NKP's approach to seeking traffic)
---- with the new goal for  Chessie, of high speed freights,and an aggressive
management seeking an ever expanding customer base.

But, they decided to take the easier route & rake-in immense amounts of cash
from the coal traffic.   And they were happy with that and their fleet of 2-6-6-6s
and their immense 2-8-4s with lots of weight, big pistons and boosters --
a money making pair of designs.

IMHO..

W



Edited 1 time(s). Last edit at 01/21/23 12:20 by wcamp1472.



Date: 01/21/23 17:30
Re: C&O H-8 question
Author: tomstp

The C&O 2-10-4's should have been fitted with box-pok drivers and light weight rods.  Since they were not, comparing them to Santa Fe 2-10-4's is not a fair comparison in addition to Santa Fe having taller  74" drivers too.



Edited 1 time(s). Last edit at 01/21/23 17:31 by tomstp.



Date: 01/21/23 19:27
Re: C&O H-8 question
Author: wcamp1472

No such thing as ‘light weight rods’..
A figment of advertising ..

Timken’s larger diameter rod ends. The numerous components for each roller bearing assembly, and the multiple tandem rods were way too heavy compared to conventional rod arrangements as on UP 800s and Challengers, as well as locos used. by other RRs like SP.

Roanoke simplified Timken’s complexity & weighting problems by eliminating the outer tandem rods, casting new, lighter driver centers with smaller counterweight cavities and applied shorter crankpins.
But Roanoke was the exception..

Such tinkering as suggested, would not have cured the outdated 2-10-4 design's limitations.
But Altoona made-do with their copies of the C&O design. As allowed by the WPB, during WW2..

Ways to lighten reciprocating components:
Anything you can do to lighten reciprocating mass, allows for lighter counter-weighting..
.. which means possibility of higher RPMs, and  higher track speeds.

Hollow piston rods: Yes.
Slimmer, lighter pistons: Yes.
Less mass in the crossheads: Yes
Lightweight rods: no such thing..
Longer, more mass crankpins: Not Lighter…
Steel is steel..

Later design, plain bearing rods are a lighter total assembly than a
complete outfit of roller-equipped set of tandem side rods, with longer
---- heavier--- crankpins, etc.

Ask Roanoke why they had to modify ( eliminate & rearrange) the rods,
make new, shorter crankpins and cast new driver centers for some J-class engines.  
( it's my speculation that only the 'modified' J-engines were capable of 
   the popular belief of a J being able to run at a maximimum of 110mph.--
   - that was its absolute upper limit)..

W.

( IMHO...
 N&W should have gone for 72" to 75" drivers for under the J class....larger divers
  allow the designers to use smaller & less mass in the driver counterweights --- as the greater
  centrifugal  forces, at high driver-RPMs, magnifies the effective weights   [ smaller weights further
   from the center] for better counter balancing.---- without the whirling weights lifting the drivers off the rails ..
   Lima/C&O J3a, 4-8-4, is a better design for high speed, high power passenger engines..)

Posted from iPhone



Edited 6 time(s). Last edit at 01/22/23 13:53 by wcamp1472.



Date: 01/23/23 08:31
Re: C&O H-8 question
Author: kurt765

Quick related side question. If an H-8 were restored in some alternate reality where such a thing was likely to happen, what challenges would it face on today's trackage? Wikipedia says the lead driving axle has a load of up to 86,700 lbs. The whole engine weighs roughly the same as a Big Boy but a little more compact. Just curious if the axle load would be an issue in today's world.
 



Date: 01/23/23 12:21
Re: C&O H-8 question
Author: junctiontower

Maybe I'm totally dense here, but seeing that a C&O 2-10-4 is just an upsized NKP Berk/C&O Kanawha which were enormously successful (Yes, I know it's actually the other way around) I fail to see how the C&O 2-10-4 is out dated and of inferior design, especially when compared to the H8, which was an overweight behemouth that was being used in totally the wrong application.  If you're the C&O, and you want to move coal upbound from the Ohio River, the the 2-10-4 seems like it was absolutely ideally suited to that task.  As for pounding the track at speed, how fast do you plan on going with 13,000 tons of coal?



Date: 01/23/23 13:42
Re: C&O H-8 question
Author: train1275

junctiontower Wrote:
-------------------------------------------------------
> Maybe I'm totally dense here, but seeing that a
> C&O 2-10-4 is just an upsized NKP Berk/C&O Kanawha
> which were enormously successful (Yes, I know it's
> actually the other way around) I fail to see how
> the C&O 2-10-4 is out dated and of inferior
> design, especially when compared to the H8, which
> was an overweight behemouth that was being used in
> totally the wrong application.  If you're the
> C&O, and you want to move coal upbound from the
> Ohio River, the the 2-10-4 seems like it was
> absolutely ideally suited to that task.  As for
> pounding the track at speed, how fast do you plan
> on going with 13,000 tons of coal?

Yeah, that is kind of the way I was looking at it and thinking about it when I asked the question.



Date: 01/23/23 13:50
Re: C&O H-8 question
Author: train1275

kurt765 Wrote:
-------------------------------------------------------
> Quick related side question. If an H-8 were
> restored in some alternate reality where such a
> thing was likely to happen, what challenges would
> it face on today's trackage? Wikipedia says the
> lead driving axle has a load of up to 86,700 lbs.
> The whole engine weighs roughly the same as a Big
> Boy but a little more compact. Just curious if the
> axle load would be an issue in today's world.
>  

I think it would have to go through engineering analysis like any other "high and wide" as it is not a standard piece of equipment, i.e. it is still big in today's world.
Height, width (including maximum swing). axle weights, total weight, length, maximum degree of curvature, etc.  and then these dimensions related to whatever trackage it is towed or run on.  Rail size, track conditions,  line clearances, bridge restrictions, speed restrictions, turnouts involved, etc. 



Date: 01/24/23 09:36
Re: C&O H-8 question
Author: tomstp

Hugh Hollis , chief mechanical officer of the Texas & Pacific, used the term "light weight rods".  I did not ask for a meaning of the statement other than what it said. He was referring to the re balancing of T&P's 63" driver 2-10-4s which included a boxpok main driver, and cross counter balancing of all drivers. Also replacement of the crosshead  and guide with a different design.  Prior to the re balancing the main driver would lift off the rail at 45 mph.  After the work was done, they would ride smooth at 70 MPH.  By the way, after the work on the 2-10-4's they did the same on 11 light USRA 2-8-2's with the same result.



[ Share Thread on Facebook ] [ Search ] [ Start a New Thread ] [ Back to Thread List ] [ <Newer ] [ Older> ] 
Page created in 0.1019 seconds